Hi Gord, there isn't really any way other than zooming in and inspecting things closely.

re: unboolean - it is possible to separate surfaces from the main piece by using Edit > Separate on them and then doing things like using "untrim" to erase trim curves. But you'll be working at the surface level for that it's not quite the same thing as an "unboolean" exactly. There is a tutorial on that kind of surface level repair work here though: http://moi3d.com/forum/index.php?webtag=MOI&msg=446.17

- Michael